xslyman

Context: models

Synopsis

The XSPEC lyman model: Voigt absorption profiles for H I or He II Lyman series.

Syntax

xslyman

The xslyman model is a multiplicative model component.

Description

The model is described at [1] .

Deprecated in Sherpa 4.10.0

The nhei and redshift parameters have been renamed to n and z respectively to match the XSPEC definition. The names nhei and redshift can still be used to access the parameters, but they will be removed in a future release.

Example

>>> create_model_component("xslyman", "mdl")
>>> print(mdl)

Create a component of the xslyman model and display its default parameters. The output is:

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.n        thawed        1e-05            0        1e+06 10^22 atoms / cm^2
   mdl.b        thawed           10            1        1e+06       km/s
   mdl.z        thawed            0       -0.001       100000           
   mdl.ZA       thawed            1            1            2

ATTRIBUTES

The attributes for this object are:

Attribute	Definition
n	The H I or He II column density, in 10^22 atoms/cm^2.
b	The b value, in km/s.
z	The redshift of the absorber.
ZA	The atomic number of the species being calculated.

References

[1]

XSPEC version

CIAO 4.18 comes with support for version 12.14.0k of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.14.0k

Bugs

See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.